test/all_pairs_shortest_path_test.cc
author alpar
Thu, 14 Sep 2006 18:39:07 +0000
changeset 2214 a886e48e0d91
parent 1763 49045f2d28d4
child 2242 16523135943d
permissions -rw-r--r--
Doc improvements
     1 /* -*- C++ -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library
     4  *
     5  * Copyright (C) 2003-2006
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #include <iostream>
    20 #include <vector>
    21 
    22 #include <cmath>
    23 #include <cstdlib>
    24 
    25 #include <lemon/smart_graph.h>
    26 #include <lemon/dijkstra.h>
    27 #include <lemon/floyd_warshall.h>
    28 #include <lemon/johnson.h>
    29 
    30 #include <lemon/fib_heap.h>
    31 
    32 #include <lemon/time_measure.h>
    33 #include "test_tools.h"
    34 
    35 using namespace lemon;
    36 using namespace std;
    37 
    38 int main(int argc, const char *argv[]) {
    39   srand(time(0));
    40   typedef SmartGraph Graph;
    41   typedef Graph::Node Node;
    42   typedef Graph::Edge Edge;
    43   typedef Graph::NodeIt NodeIt;
    44   typedef Graph::EdgeIt EdgeIt;
    45 
    46   typedef Graph::EdgeMap<double> LengthMap;
    47   typedef Graph::NodeMap<double> DistMap;
    48 
    49   const int n = argc > 1 ? atoi(argv[1]) : 20;
    50   const int e = argc > 2 ? atoi(argv[2]) : (int)(n * log((double)n));
    51   const double m = argc > 3 ? (double)atoi(argv[3]) : 100.0;
    52 
    53   Graph graph;
    54   LengthMap length(graph);
    55   vector<Node> nodes;
    56   
    57   DistMap shift(graph);
    58   for (int i = 0; i < n; ++i) {
    59     Node node = graph.addNode();
    60     nodes.push_back(node);
    61     shift[node] = m * (double)rand() / (RAND_MAX + 1.0);
    62   }
    63 
    64   for (int i = 0; i < e; ++i) {
    65     int s = (int)(n * (double)rand() / (RAND_MAX + 1.0));
    66     int t = (int)(n * (double)rand() / (RAND_MAX + 1.0));
    67     double c = m * (double)rand() / (RAND_MAX + 1.0);
    68     Edge edge = graph.addEdge(nodes[s], nodes[t]);
    69     length[edge] = c - shift[nodes[s]] + shift[nodes[t]];
    70   }
    71 
    72   Johnson<Graph, LengthMap> johnson(graph, length);
    73   {
    74     Timer timer;
    75     johnson.run();
    76     cout << "Johnson: " << timer << endl;
    77   }
    78 
    79   typedef FibHeap<Node, double, Graph::NodeMap<int> > DoubleFibHeap;
    80   Johnson<Graph, LengthMap>::DefStandardHeap<DoubleFibHeap>
    81     ::Create fibJohnson(graph, length);
    82   {
    83     Timer timer;
    84     fibJohnson.run();
    85     cout << "Johnson with fibonacci heap: " << timer << endl;
    86   }
    87 
    88   FloydWarshall<Graph, LengthMap> floyd(graph, length);
    89   {
    90     Timer timer;
    91     floyd.run();
    92     cout << "FloydWarshall: " << timer << endl;
    93   }    
    94 
    95   for (NodeIt it(graph); it != INVALID; ++it) {
    96     for (NodeIt jt(graph); jt != INVALID; ++jt) {
    97       check(johnson.connected(it, jt) == floyd.connected(it, jt),
    98 	    "Wrong connection in all pairs shortest path");
    99       check(johnson.connected(it, jt) == fibJohnson.connected(it, jt),
   100 	    "Wrong connection in all pairs shortest path");
   101       if (johnson.connected(it, jt)) {
   102 	check(johnson.dist(it, jt) == floyd.dist(it, jt),
   103 	      "Wrong distance in all pairs shortest path");
   104 	check(johnson.dist(it, jt) == fibJohnson.dist(it, jt),
   105 	      "Wrong distance in all pairs shortest path");
   106 	if (it != jt) {
   107  	  check(johnson.dist(it, jt) == 
   108 		johnson.dist(it, johnson.predNode(it, jt)) +
   109 		length[johnson.predEdge(it, jt)],
   110 		"Wrong edge in all pairs shortest path");
   111  	  check(fibJohnson.dist(it, jt) == 
   112 		fibJohnson.dist(it, fibJohnson.predNode(it, jt)) +
   113 		length[fibJohnson.predEdge(it, jt)],
   114 		"Wrong edge in all pairs shortest path");
   115 	  check(floyd.dist(it, jt) == 
   116 		floyd.dist(it, floyd.predNode(it, jt)) +
   117 		length[floyd.predEdge(it, jt)],
   118 		"Wrong edge in all pairs shortest path");
   119 	}
   120       }
   121     }
   122   }
   123 
   124   return 0;
   125 }